Term
| Alzheimer's, Clinical Depression, and Parkinson's? |
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Definition
| Alzheimers- associated with the decreased levels of acetylcholine and associated with the accumulation of abnormal protein, beta amyloid. CD- associated with decreased levels of serotonin, dopamine, and norepinephrine. Parkinson's- associated with decreased level of dopamine. |
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Term
| 3 Different neurotransmitters are associated with different behavioral systems? |
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Definition
| Norepinephrine, serotonin, dopamine. |
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Term
| Norepinephrine, serotonin, and dopamine? |
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Definition
| Norepinephrine- regulates mood, hunger, thirst, and sex drive. Serotonin- promotes a feeling of well-being. Dopamine- regulates emotions and complex movements. |
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Term
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Definition
| Acts in both PNS and CNS, release at every neuromuscular junction. Myasthenia gravis- autoimmune disease that attacks the acetylcholine receptors at neuromuscular junctions, resulting in little muscle strength. |
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Term
| Function of the nervous system? |
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Definition
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Term
| Two types of specialized cells? |
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Definition
| Neurons and Neuroglial cells. |
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Term
| Neurons and Neuroglial cells? |
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Definition
| Neurons- Excitable cells that generate and transmit messages. Neuroglial cells- Provide structural support, growth factors, and insulating sheaths around axons. |
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Term
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Definition
| Sensory, motor, Interneurons. |
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Term
| Functions of Sensory, Motor, and Interneurons? |
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Definition
| Sensory- carry information toward the CNS from sensory receptors. Motor- carry information away from the CNS to an effector (muscle or gland). Interneurons- Found only in the brain and spinal cord. between sensory and motor neurons, intergrate and interpret sensory signals. |
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Term
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Definition
| Dendrites- many short, branching projections. Axon- a single long extension. cell body. |
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Term
| Functions of Dendrites, Axons, and Cell body? |
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Definition
| Dendrites- Receives signals from other cells, carries info toward the cell body of a neuron. Axon- carries info away from the cell body to either another neuron or an effector. Cell body- contains nucleus and other organelles |
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Term
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Definition
| consists of parallel axons, dendrites, or both from many neurons. Covered with tough connective tissue. Classified as sensory, motor, or mixed depending on the type of neurons they contain. |
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Term
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Definition
| provides electrical insulation that increases the rate of conduction of a nerve impulse. composed of plasma membranes of glial cells. In the PNS, Schwann cells (a type of glial cell) form the myelin sheath. |
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Term
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Definition
| Gaps between adjacent schwann cells. Messages travel faster as they jump from one ode of ranvier to the next in a type of transmission called salutatory conduction. |
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Term
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Definition
| A disease in which the myelin sheaths in the brain and spinal cord are progressively destroyed. Results from the destruction of the myelin sheath that surrounds axons in the cns. the resulting scars (scleroses) interfere with the transmission of nerve impulses. can result in paralysis and loss of sensation, including loss of vision. |
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Term
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Definition
| a nerve impulse, or action potential, is an electrochemical signal involving sodium and potassium ions that cross the cell membrane through ion channels. each ion channel is designed to allow only certain ions to pass through it. sodium channels permit sodium ions to pass, Potassium channels permit potassium ions to pass. Ion Channels may be permanently open or regulated by a "gate", which is a protein that changes shape and opens or closes a channel. The transport does not require any energy as the ions follow a gradient of concentration. Ions also are transported across the membrane by the sodium-potassium pump. |
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Term
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Definition
| Special proteins in the cell membrane that actively transport sodium and potassium ions across the membrane against their concentration gradients. These pumps use cellular energy to eject sodium ions from within the cell and to bring potassium ions into the cell. |
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Term
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Definition
| when a neuron is not conducting a nerve impulse, it is in a resting state called resting potential. the inner surface of the membrane is more negative than the outer surface. (due to large anions trapped inside cell). There are more sodium ions inside the membrane than outside. There are more potassium ions outside the membrane than outside. this state is maintained by the sodium-potassium pump. |
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Term
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Definition
| when the neuron is stimulated, there is a sudden reversal of charge across the membrane because the sodium gates open and sodium ions enter the cell. Next, the potassium gates open and potassium ions rush out of the cell. This causes the cell to return to its original state. these changes occur in a wave along the axon. Does not diminish once started. Does not vary in intensity with the strength of the stimulus that triggered it. Is 'all-or-nothing". for a brief period following an action potential, the neuron cannot be stimulated again. this is called the refractory period. It occurs because the sodium channels are closed and cannot be reopened. |
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Term
| Threshold, depolarization and repolarization? |
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Definition
| Threshold- minimum charge that causes the sodium gates to open. Depolarization- reduction of the charge difference across the membrane. Repolarization- restoration of the charge difference across the membrane. |
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Term
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Definition
| communication between a neuron and an adjacent cell occurs by neurotransmitters. Synapse - junction between a neuron and another cell. |
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Term
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Definition
| Gap between two cells, neurotransmitters diffuse across the gap. In the case two neurons, the presynaptic neuron sends a message to the postsynaptic neuron. The synaptic knob is the swelling at the end of the axon of the presynaptic neuron. |
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Term
| Release of the neurotransmitter and the opening of ion transmitters? |
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Definition
| The nerve impulse reaches the synaptic knob of the presynaptic neuron. Calcium ions move into the synaptic knob which releases the neurotransmitter into the synaptic cleft. the neurotransmitter diffuses across the synaptic cleft and binds with receptors on the membrane of the postsynaptic neuron causing an ion channel to open. At an excitatory synapse, binding of the neurotransmitter to the recetor causes sodium channels to open increasing the likelihood that an action potential will begin. At an inhibitory synapse , binding of the neurotransmitter to the receptor opens different ions channels. The postsynaptic cells interior becomes more negatively charged than usual, reducing the likelihood that an action potential will begin. |
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Term
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Definition
| combined effects of excitatory and inhibitory effects at any given moment. Determines whether an action potential is generated. this level of integration provides fine control over neuronal responses. |
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Term
| removal of Neurotransmitters? |
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Definition
| once released into a synapse, neurotransmiteers are quickly removed. some are deactivated by enzymes. the enzymes acetylcholinesterase removes acetylcholine from synapses. other are pumped back into the synaptic knob of the presynaptic axon. |
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